CVE-2025-59419 (GCVE-0-2025-59419)

Vulnerability from cvelistv5 – Published: 2025-10-15 15:42 – Updated: 2025-10-17 19:44
VLAI
Title
Netty netty-codec-smtp SMTP Command Injection Vulnerability Allowing Email Forgery
Summary
Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.128.Final and 4.2.7.Final, the SMTP codec in Netty contains an SMTP command injection vulnerability due to insufficient input validation for Carriage Return (\r) and Line Feed (\n) characters in user-supplied parameters. The vulnerability exists in io.netty.handler.codec.smtp.DefaultSmtpRequest, where parameters are directly concatenated into the SMTP command string without sanitization. When methods such as SmtpRequests.rcpt(recipient) are called with a malicious string containing CRLF sequences, attackers can inject arbitrary SMTP commands. Because the injected commands are sent from the server's trusted IP address, resulting emails will likely pass SPF and DKIM authentication checks, making them appear legitimate. This allows remote attackers who can control SMTP command parameters (such as email recipients) to forge arbitrary emails from the trusted server, potentially impersonating executives and forging high-stakes corporate communications. This issue has been patched in versions 4.1.129.Final and 4.2.8.Final. No known workarounds exist.
Severity
5.5 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-15 17:21 UTC
CWE
  • CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8038 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
netty netty Affected: < 4.2.7.Final
Affected: >= 4.2.0.Alpha1, < 4.1.128.Final
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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